Software

The Atari
archives can occasionally come up with information relevant to
PC GEM. In particular, I recommend
Professional GEM, a series of articles on GEM development.
They're aimed at Atari GEM, but PC GEM is similar enough that
nearly all the information comes across.

Shaneland OpenGEM is
a distro of Intel GEM that's probably the best choice to install on
modern PCs.

Heinz
Rath's pages contain a VESA 800x600 driver, the ViewMAX/3
desktop, and the start of a web browser for GEM.

QuickMap is a
program for the entry and manipulation of geographic data. It uses
GEM drivers for display and printing; though it looks just like a normal
GEM application, it has actually re-implemented most of GEM internally.